Altitude sickness can strike anyone who ascends from a relatively low altitude (for example sea level) to a relatively high altitude (for example 8,000 feet or more). Some visitors to the Rocky Mountains (as well as to other mountain ranges) suffer from altitude sickness. Symptoms of altitude sickness include headaches, dizziness, and shortness of breath.
The human body typically needs to acclimate to the lower oxygen levels of high altitudes. One way to obtain quick relief of altitude sickness is to breathe concentrated oxygen. This increases the level of oxygen in the blood.
Concentrated oxygen is available through medical services providers (ambulances, hospitals, etc.). Consequently, its use is restricted to those that also require medical assistance. There are however, situations where someone may wish to breathe concentrated oxygen without summoning medical assistance.